imx: Race when disabling RX in IMX.6 UART in half duplex

[Fabio Estevam]

Hi Piotr,

On Tue, Feb 21, 2017 at 5:48 AM, Piotr Figiel
<p.figiel at camlintechnologies.com> wrote:

> I'm not sure if it's best idea, I don't know if the UART will keep
> triggering the interrupt if the source won't be cleared (FIFO drained), but
> if it does we'll be irq flooded, if it doesn't there will be old contents in
> the RX fifo no-one will touch until some other interrupt (other than TX fifo
> empty, as at that time RXEN would still be 0) comes. RX fifo could be
> alternatively cleaned somewhere else, this is actually question I raise in
> my initial e-mail.

How does the half-duplex RS485 problem manifest in practice?

Do you think the issue you see is similar to what Clemens reported at:
https://lkml.org/lkml/2017/1/4/579 ?

Also, could you try kernel 4.10 instead of 3.10 so that we are all in
the same code base?

Thanks